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Facts About Sierra Nevada
Sierra Nevada is a mountain range in eastern California. It is the site of three national parks -Yosemite, Sequoia, and Kings Canyon- and of beautiful Lake Tahoe, whose clear, blue waters reach depths of more than 1,600 feet (490 meters). The name Sierra Nevada is Spanish for "snowy saw-toothed range."
The Sierra Nevada is a great granite block extending 430 miles (692 km) south from the Feather River to Tehachapi Pass. The uplift and tilting to the west of a huge segment of the earth's crust produced a long, gradual slope on the west and a near-vertical escarpment on the east. The peaks increase in altitude from Lake Tahoe (6,225 feet, or 1,898 meters) southward to Mt. Whitney (14,496 feet, or 4,418 meters), the highest peak in the United States outside Alaska. From Mt. Whitney, the altitude of the peaks gradually decreases to the south end of the range.
Awe-inspiring canyons have been deeply incised into the long western slope by a number of rivers, including the Feather, American, Tuolumne, Merced, San Joaquin, Kings, and Kern. On the shorter, steeper eastern slope many creeks descend to join the Owens, Walker, Carson, and Truckee rivers. Mountain glaciation played a part in shaping bold, impressive landscapes in the Sierra Nevada. Sheer cliffs, meadows, lakes, and high leaping waterfalls, such as one sees in Yosemite Valley, add beauty to the range.
Rainfall increases with the elevation up to 4,500 feet (1,350 meters), then decreases to the crest of the range. Beyond the summit on the eastern slope, the rainfall is less. Winter snowfall is heavy. Annual amounts of 30 to 40 feet (9–12 meters) are normal near Lake Tahoe and Donner Pass, and seasonal snowfalls of up to 60 feet (18 meters) have been recorded.
Life zones occur in a belted arrangement. At the west base of the range, adjacent to the Sacramento and San Joaquin valleys, grasses and shrubs are dominant. At elevations of 3,000 to 4,000 feet (900–1,200 meters) grow great forests of commercially valuable timber, composed of yellow pine, sugar pine, incense cedar, and fir. In scattered groves within the forest is found the Sequoia gigantea, or "big tree," considered the largest member of the earth's flora. At 6,000 to 7,000 feet (1,800–2,150 meters) occur lodgepole pine, Jeffrey pine, and red fir. Near the 9,000-foot (2,750–meter) level, only the hardier specimens are found. Above the timberline the rocky terrain is essentially bare of vegetation. The dry east slopes support scattered trees in intermediate elevations, and at the foot of the range sagebrush and other shrubs merge with desert types of vegetation.
West slope rivers supply irrigation water to farmlands in the Sacramento and San Joaquin valleys and the Tulare Basin. California's largest cities secure municipal water from these rivers, and hydroelectric plants on the rivers and on the aqueducts that lead from them generate power for the state's farms and metropolitan areas.
The Sierra Nevada interposes a barrier 40 to 80 miles (65–130 km) wide to east-west travel. Vehicles can cross the range only over particular passes. Major highways utilize the following passes: Beckwourth (5,250 feet, or 1,600 meters), Donner (7,135 feet, or 2,175 meters), Carson (8,600 feet, or 2,620 meters), Ebbetts (8,800 feet, or 2,680 meters), Sonora (9,625 feet, or 2,935 meters), and Walker (5,248 feet, or 1,600 meters). A road over Tioga Pass (9,625 feet, or 3,030 meters) connects Yosemite Valley and Mono Lake, but it is generally closed due to heavy snow for 9 months of the year. The Western Pacific and Southern Pacific railroad companies laid track over Beckwourth Pass and also over Donner Pass. Mountain trails used by hikers and pack trains cross the range. John Muir Trail along the mountain crest opens up the wilderness of the High Sierras.
The discovery of gold in the Sierra Nevada started the 1849 gold rush and attracted a large population to the foothill zone. But mining of gold and other metals is no longer important. Tourism is the largest industry of the region, and there are camping and recreation facilities of all sorts throughout the mountains. Both summer resorts and winter sports centers abound. Other economic activities include fruit growing, in the western foothills, and lumbering and grazing, on the intermediate slopes.